The present invention relates to treatment of abnormalities in a patient's vascular system. A specific use of the present invention described below is for the treatment of cerebral aneurysms although the various aspects of the invention described below may also be useful in treating other abnormalities such as arteriovenous malformations (AVM), hypervascular tumors, cavernous carotid fistulas, fibroid tumors, and non-reversible sterilisation via fallopial occlusion.
Cerebral aneurysms are enlargements of the cerebral vasculature, which protrude like a balloon from the wall of a cerebral artery. The cerebral aneurysm has a neck, which leads to the parental vessel and a body or “dome” which can vary in diameter from 1-30 mm.
The wall of the aneurysm is often weak and can rupture, leading to hemorrhage. Rupture of the aneurysm can kill the patient or leave the patient with permanent or transitory mental and physical deficits.
Aneurysms are often treated to prevent rupture, leading to hemorrhage, or to prevent rebleeding of acutely ruptured aneurysms. A conventional method of treating aneurysms is to fill the aneurysm with coils. The coils are introduced into the aneurysm one at a time through a delivery catheter until the aneurysm is filled. The aneurysm eventually becomes a solid mass of coils and thrombus.
A problem with the conventional method of using coils to fill aneurysms is that the aneurysm becomes a relatively solid mass due to coils and thrombus contained therein. The mass of coil and thrombus exerts pressure on adjacent areas of the brain, which may lead to other problems. Another problem with the conventional method is that the coils must be delivered one at a time into the aneurysm, which increases the procedure time and risk to the patient. For large aneurysms, up to twenty coils may be required to fill the aneurysm.
It is an object of the invention to provide improved methods and devices for treating aneurysms. These and other objects of the invention will become evident from the description of the preferred embodiments described below.